1. Field of the Invention
The present invention relates generally to a method of manufacturing a magnetic recording medium and an opto-magnetic recording medium, and especially to a magnetic tape, a magnetic disc, an opto-magnetic disc, a magnetic card or the like, and furthermore relates to methods of manufacturing an amorphous magnetic recording medium and an abrasion-resistive magnetic recording medium.
2. Description of the Prior Art
A typical conventional magnetic recording medium is classified into two types. One is a coated type and other is a vacuum deposited type. In respect to the coated type magnetic recording medium, generally, a kind of paint prepared by dispersing magnetic powder of Fe.sub.2 O.sub.3 or .gamma.-Fe.sub.2 O.sub.3 added with Co in a mixture of polyvinyl-butyral, toluene and methyl-iso-butyl-ketone etc., is coated on a substrate 4-5 .mu.m thick. Though the above-mentioned process is easy, there is a limitation in decreasing particle size of the magnetic powder, and no sufficient characteristic has been expected for a high density recording.
On the other hand, as to a vacuum deposition type, the density of the recording is better than that of the coating type of magnetic recording medium, there is a problem of insufficient durability, since a ferromagnetic metal layer is exposed on a surface of the substrate. In order to improve it, a proposal has been made that on a 1000-2000.ANG. thick metal layer formed by electron beam method or a spattering, an overcoating is carried out, and further thereon a lubricant is coated. Nevertheless, in the present situation, its durability has not yet been sufficient. In addition thereof, a magnetic field of a recording head needs to be considerably strengthened as a result of providing of such an overcoat or a lubricant layer.